Carbonless duplicating and marking systems

ABSTRACT

Dialkylamino-substituted 2-anilino-5&#39;/6&#39;-carboxyfluorans, esterified dialkylamino-substituted 2-anilino-5&#39;/6&#39;-carboxyfluorans and 3,3-(corresponding-substituted-diaryl)-5/6-carboxyphthalides useful as color formers, particularly in carbonless duplicating and thermal marking systems, are prepared by the interaction of 4/5-carboxy-2-(4-dialkylamino-substituted-2-hydroxybenzoyl)benzoic acids and substituted diphenylamines to produce the phthalides which are then subjected to ring closure to produce the carboxyfluorans which are esterified with alkyl halides or dialkyl sulfates.

BACKGROUND OF THE INVENTION

(a) Field of the Invention

This invention relates to novel compounds classified in the field oforganic chemistry as fluorans useful as color precursors, particularlyin the art of carbonless duplicating, for example, pressure-sensitiveand thermal marking systems; to3,3-(substituted-diaryl)-5/6-carboxyphthalides useful as intermediatesto the subject fluoran color precursors; to processes for preparing saidfluorans and phthalides; and to pressure-sensitive duplicating systemsand thermal marking systems.

(b) Description of the Prior Art

Several classes of organic compounds of widely diverse structural typesare known to be useful as colorless precursors for carbonlessduplicating systems. Among the more important classes, there may benamed phenothiazines, for example, benzoyl leuco methylene blue;phthalides, for example, crystal violet lactone; fluorans, for example,with which this invention is concerned, for example,2'-anilino-6'-diethylaminofluoran and2'-dibenzylamino-6'-diethylaminofluoran; and various other types ofcolorless precursors currently employed in commercially acceptedcarbonless copy systems. Typical of the many such systems taught in theprior art are those described in U.S. Pat. Nos. 2,712,507, 2,800,457 and3,041,289 which issued July 5, 1955, July 23, 1957 and June 26, 1962,respectively. Many of the color formers in the prior art suffer one ormore disadvantages such as low tinctorial strength, poor lightstability, low resistance to sublimation, low susceptibility tocopiability of the color-developed form in standard copying machines,for example, a Xerox® copier, and low solubility in common organicsolvents, the latter disadvantages thus requiring the use of specializedand expensive solvents in order to obtain microencapsulated solutions ofsufficient concentration for use in pressure-sensitive copying systems.

The following items to date appear to constitute the most relevant priorart with regard to the instant invention.

U.S. Pat. No. 4,104,437, issued Aug. 1, 1978, discloses and claims apressure-sensitive copy system bearing pressure-rupturable microcapsulescontaining a chromogenic compound having the formula ##STR1## andcontaining additionally in admixture a chromogenic precursor having theformula ##STR2## wherein R¹ and R² each represent an alkyl group; R³ andR⁴ each represent a hydrogen atom; a halogen atom, an alkyl group, anitro group, an amino group, an acyl group, or a carboalkoxy group; R⁵represents a hydrogen atom or an alkyl group, with the proviso that R⁵represents an alkyl group only when R⁴ represents a hydrogen atom; R⁶represents an alkyl group, an aryl group or an aralkyl group; and X andY each represent a hydrogen atom, a halogen atom, a nitro group, a loweralkyl group, an aryl group, an alkoxy group, or a carboalkoxy group.

British Pat. No. 1,427,318, issued Mar. 10, 1976, discloses a fluoranhaving the formula ##STR3##

German Offenlegungschrift No. 2,242,005 which was published Mar. 15,1973, discloses a process for the preparation of phthalides of theformula ##STR4## by interacting a 2-hydroxy oralkoxy-4-dialkylamino-2'-carboxybenzophenone with a phenol of theformula ##STR5## wherein R is hydrogen or alkyl and R₂ is hydrogen,phenyl or phenyl substituted by alkyl in the presence of sulfuric acidat 10°-30° C. for 2-5 hours and then making alkaline to pH 8-10.5 toisolate the phthalide. Alternatively, by adjusting the pH to 10-11,heating the alkaline reaction mixture at 80°-100° C., the correspondingfluorans are formed. The compounds have disclosed utility as colorformers for pressure-sensitive papers.

SUMMARY OF THE INVENTION

The present invention provides for novel fluorans selected from amongsubstituted 2-anilino-5'/6'-carboxyfluorans,2-anilino-5'/6'-alkoxycarbonylfluorans and2-anilino-5'/6'-phenylmethoxycarbonylfluorans which are useful as colorformers in pressure-sensitive duplicating systems and in thermal markingsystems. The compounds develop colored images of good to excellenttinctorial strength, and have the advantages of good light stability andenhanced solubility in common organic solvents. The present inventionalso provides 3,3-(substituted diaryl)-5/6-carboxyphthalides useful asintermediates to the subject fluoran color formers which are also usefulas color formers for thermal marking systems.

In one of its composition of matter aspects the invention relates to aseries of 2-anilino-3-R¹ -6-(R)₂ amino-5'/6'-Y-carbonylfluorans whichare useful as color formers in pressure-sensitive carbonless duplicatingsystems and thermal marking systems.

In a second of its composition of matter aspects, the invention relatesto a series of 3-[2-hydroxy-4-(R)₂ aminophenyl]-3-(2-R³ -4-R¹-5-anilinophenyl)-5/6-carboxyphthalides which are useful asintermediates for the preparation of the fluoran final products of theinvention and which are also useful as color formers for thermal markingsystems.

In one of its process aspects, the invention relates to a process forpreparing 2-anilino-3-R¹ -6-(R)₂ amino-5'/6'-carboxyfluoran whichcomprises heating a 3-[2-hydroxy-4-(R)₂ aminophenyl]-3-(2-R³ -4-R¹-5-anilinophenyl)-5/6-carboxyphthalide in the presence of an alkalimetal hydroxide.

In a second of its process aspects, the invention relates to a processfor preparing 2-anilino-3-R¹ -6-(R)₂ amino-5'/6'-alkoxycarbonyl- orphenylmethoxycarbonylfluorans which comprises esterifying thecorresponding 2-anilino-3-R¹ -6-(R)₂ amino-5'/6'-carboxyfluoran with anappropriate alkylating agent in the presence of an alkali.

In a third process aspect, the invention relates to a process forpreparing a 3-[2-hydroxy-4-(R)₂ aminophenyl]-3-(2-R³ -4-R¹-5-anilinophenyl)-5/6-carboxyphthalide which comprises interacting theappropriate 4/5-carboxy-2-[4-(R)₂ amino-2-hydroxybenzoyl]benzoic acidwith the appropriate 2-R¹ -4-R³ -diphenylamine in the presence ofsulfuric acid.

The present invention provides in one of its article of manufactureaspects, pressure-sensitive carbonless duplicating systems and thermalmarking systems each containing at least one color forming substancecomprising a 2-anilino-3-R¹ -6-(R)₂ amino-5'/6'-Y-carbonylfluoran.

In a second article of manufacture aspect, the invention relates tothermal marking systems each containing at least one color-formingsubstance comprising a 3-[2-hydroxy-4-(R)₂ aminophenyl]-3-(2-R³ -4-R¹-5-anilinophenyl)-5/6-Y-carbonylphthalide.

DETAILED DESCRIPTION INCLUSIVE OF THE PREFERRED EMBODIMENTS

More specifically, this invention in one of its composition of matteraspects relating to final products, resides in the novel fluorans, whichare particularly useful as colorless precursors in the art of carbonlessduplicating and thermal marking, and which are selected from the groupconsisting of 2-anilino-3-R¹ -6-(R)₂ amino-5'/6'-Y-carbonylfluoranhaving the formula ##STR6## wherein: R represents a non-tertiary C₁ toC₄ alkyl;

R¹ represents hydrogen or a non-tertiary C₁ to C₄ alkyl; and

Y represents OR² in which R² represents hydrogen, a non-tertiary C₁ toC₁₈ alkyl, benzyl, alkali metal cation or ammonium cation.

In a first particular embodiment in accordance with its final productcomposition of matter aspect, the invention sought to be patentedresides in the novel 2-anilino-3-R¹ -6-(R)₂ amino-5'/6'-carboxyfluoransof Formula I wherein Y is OH and R and R¹ each have the same respectivemeanings given in Formula I.

In a second particular embodiment in accordance with its firstcomposition of matter aspect, the invention sought to be patentedresides in the novel 2-anilino-3-R¹ -6-(R)₂ amino-5'/6'-R²O-carbonylfluorans of Formula I wherein Y is R² O and R² representsnon-tertiary C₁ to C₁₈ alkyl or benzyl and R and R¹ each have the samerespective meanings given in relation to Formula I.

This invention, in a second of its composition of matter aspects,relating to intermediates to the fluorans and to final products usefulas color formers in thermal marking systems, resides in the novel3-[2-hydroxy-4-(R)₂ aminophenyl]-3-(2-R³ -4-R¹-5-anilinophenyl)-5/6-carboxyphthalides having the formula ##STR7##wherein: R represents a non-tertiary C₁ to C₄ alkyl;

R¹ represents hydrogen or a non-tertiary C₁ to C₄ alkyl; and

R³ represents a non-tertiary C₁ to C₄ alkoxy

In a particular embodiment in accordance with its second composition ofmatter aspect, the invention sought to be patented resides in the novel3-[2-hydroxy-4-(R)₂ aminophenyl]-3-(2-R³ -4-R¹-5-anilinophenyl-5/6-carboxyphthalides of Formula II wherein R, R¹ andR³ L each have the same respective meaning given in relation to FormulaII.

In one of its process aspects, the invention sought to be patentedresides in a process for preparing a 2-anilino-3-R¹ -6-(R)₂amino-5'/6'-carboxyfluoran according to Formula I which comprisesheating a 3-[2-hydroxy-4-(R)₂ aminophenyl]-3-(2-R³ -4-R¹-5-anilinophenyl)-5/6-carboxyphthalide of Formula II in the presence ofan alkali metal hydroxide to effect ring closure wherein R³ represents anon-tertiary C₁ to C₄ alkoxy and R and R¹ each have the same respectivemeanings given in relation to Formula I.

In a second of its process aspects, the invention sought to be patentedresides in the process for preparing a 2-anilino-3-R¹ -6-(R)₂amino-5'/6'-R² O-carbonylfluoran according to Formula I wherein R²represents a non-tertiary C₁ to C₁₈ alkyl or benzyl and wherein R and R¹each have the same respective meanings given in relation to Formula Iwhich comprises esterifying the corresponding 2-anilino-3-R¹ -6-(R)₂amino-5'/6'-carboxyfluoran with an appropriate compound selected fromthe group consisting of dimethylsulfate, diethyl sulfate or R² -halogenin which R² is non-tertiary C₁ to C₁₈ alkyl or benzyl in the presence ofan alkali metal hydroxide or carbonate.

In a third ot its process aspects, the invention sought to be patentedresides in the process for preparing a 3-[2-hydroxy-4-(R)₂aminophenyl]-3-(2-R³ -4-R¹ -5-anilinophenyl)-5/6-carboxyphthalideaccording to Formula II which comprises interacting a4/5-carboxy-2-[4-(R)₂ amino-2-hydroxybenzoyl]benzoic acid withapproximately one molecular proportion of a 2-R¹ -4-R³ diphenylamine inthe presence of sulfuric acid wherein R, R¹ and R³ each have the samemeanings given in relation to Formula II.

In an article of manufacture aspect, the invention sought to be patentedresides in a pressure-sensitive or thermal marking system containing asa color-forming substance a 2-anilino-3-R¹ -6-(R)₂amino-5'/6'-Y-carbonylfluoran according to Formula I wherein R, R¹ and Yeach have the same respective meanings given relative to Formula I.

In a particular embodiment in accordance with its first article ofmanufacture aspect, the invention sought to be patented resides in apressure-sensitive transfer sheet, adapted for use with a receivingsheet having an electron accepting layer, comprising a support sheetcoated on one side with a layer of pressure-rupturable microcapsules,said microcapsules containing a liquid solution of a color formingsubstance comprising at least one compound having Formula I.

Another particular embodiment in accordance with its first article ofmanufacture aspect, resides in a heat responsive record materialcomprising a support sheet coated on one side with a layer containing amixture comprising at least one color-forming compound having Formula Iand an acidic developer arranged such that application of heat willproduce a mark-forming reaction between the color-forming compound andthe acidic developer.

Preferred articles within the ambit of the particular embodimentsabove-described are those wherein the color-forming component comprisesa 2-anilino-3-R¹ -6-(R)₂ amino-5'/6'-R² O-carbonylfluoran according toFormula I in which Y is R² O wherein R, R¹ and R² each have the samerespective meanings given in relation to Formula I.

In a second article of manufacture aspect, the invention sought to bepatented resides in a thermal marking system containing as acolor-forming substance a 3-[2-hydroxy-4-(R)₂ -aminophenyl]-3-(2-R³-4-R¹ -5-anilinophenyl)-5/6-carboxyphthalide according to Formula IIwherein R, R¹ and R³ each have the same respective meanings given inrelation to Formula II.

In a particular embodiment in accordance with its second article ofmanufacture aspect, the invention resides in a heat responsive recordmaterial comprising a support sheet coated on one side with a layercontaining a mixture comprising at least one color-forming compoundhaving Formula II and an acidic developer arranged such that applicationof heat will produce a mark-forming reaction between the color-formingcompound and the acidic developer.

As used herein the terms "non-tertiary C₁ to C₄ alkyl", and"non-tertiary C₁ to C₁₈ alkyl" denote saturated monovalent straight orbranched aliphatic hydrocarbon radicals including methyl, ethyl, propyl,isopropyl, butyl, isobutyl, amyl, 1-methylbutyl, 3-methylbutyl, hexyl,isohexyl, heptyl, isoheptyl, octyl, isooctyl, 2-ethylhexyl, nonyl,3-ethylheptyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl,n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl,1,3,5-trimethylhexyl, 1,5-dimethyl-4-ethylhexyl, 5-methyl-2-butyl-hexyl,2-propylnonyl, 2-butyloctyl, 2-pentylnonyl, 1,2-dimethylhexadecyl, andthe like.

As used herein the term "alkali metal cation" includes lithium, sodiumand potassium cations.

The term "non-tertiary C₁ to C₄ " alkoxy includes saturated, acyclic,straight or branched-chained groups such as methoxy, ethoxy, propoxy,isopropoxy, butoxy, sec-butoxy and isobutoxy.

The novel compounds of Formula I hereinabove are essentially colorlessin the depicted form. When contacted with an acidic medium, for example,silica gel or one of the types ordinarily employed in pressure-sensitivecarbonless duplicating systems such as silton clay or phenolic resinsthe compounds of Formula I develop a green to a black-colored image ofgood to excellent tinctorial strength, and possessing excellent lightstability, resistance to sublimation and xerographic copiability. Thecompounds are thus highly suitable for use as colorless precursors, thatis colorforming substances in pressure-sensitive carbonless duplicatingsystems. The black colors can be used alone as color formers to produceimages which are readily copiable, whereas the green colors can be usedas toners in admixture with other color formers to produce images of aneutral shade which desirable are readily copiable by xerographic means.Moreover, the compounds of Formula I, in particular those wherein R⁶represents C₁ to C₁₈ alkyl have enhanced solubility in common andinexpensive organic solvents such as odorless mineral spirits, kerosene,vegetable oils and the like thereby avoiding the need for moreexpensive, specialized solvents such as polyhalogenated or alkylatedbiphenyls which have ordinarily been used to prepare microencapsulatedsolutions of the color formers of the prior art.

The compounds of this invention may be incorporated in any of thecommercially accepted systems known in the carbonless duplicating art. Atypical technique for such application is as follows. Solutionscontaining one or more colorless precursor compounds of Formula I,optionally in admixture with other color formers, in suitable solventsare microencapsulated by well-known procedures for example as describedin U.S. Pat. No. 3,649,649. The microcapsules are coated on the reverseside of a transfer sheet with the aid of a suitable binder and thecoated transfer sheet is then assembled in a manifold with themicrocapsule coated side in contact with a receiving sheet coated withan electron accepting substance, for example, silton clay or a phenolicresin. Application of pressure to the manifold such as that exerted by astylus, typewriter or other form of writing or printing causes thecapsules on the reverse side to rupture. The solution of the colorformer released from the ruptured microcapsules flows to the receivingsheet and on contact with the acidic medium thereon forms green toblack-colored images of good tinctorial strength. It is, of course,obvious that variants of this mode of application can be utilized. Forexample, the receiving sheet in a manifold can alternatively be coatedwith the subject compounds and the acidic developing agent can becontained in microcapsules applied to the reverse side of the top sheetin the manifold; or the receiving sheet can be coated with a mixturecontaining both the acidic developing agent and the microencapsulatedcolor former.

It has also been found that when the compounds of Formulas I and II areintimately mixed with an acidic developer of the type generally employedin thermal papers such as described in U.S. Pat. No. 3,539,375, that is,papers which produce a colored image when contacted with a heated stylusor heated type, for example, bisphenol A, heating of the mixtureproduces a colored image of varying shades from green to black dependingon the particular compound of the invention employed. The ability of thecompounds of Formulas I and II to form a deep color when heated inadmixture with an acidic developer such as bisphenol A, makes themuseful in thermal paper marking systems, either where an original or aduplicate copy is prepared by contacting the thermal paper with a heatedstylus or heated type in any of the methods generally known in the art.

The best mode contemplated by the inventors of carrying out thisinvention will now be described so as to enable any person skilled inthe art to which it pertains to make and use the same.

In accordance with one of the process aspects of this invention the3-[2-hydroxy-4-(R)₂ aminophenyl]-3-(2-R³ -4-R¹-5-anilinophenyl)-5/6-carboxyphthalides of Formula II are obtained byinteracting in approximately equimolecular proportions an appropriate4/5-carboxy-[4-(R)₂ amino-2-hydroxybenzoyl]benzoic acid with anappropriate 2-R¹ -4-R³ -diphenylamine. The reaction is convenientlycarried out in a dehydrating solvent, for example, a mixture of 100percent sulfuric acid and oleum at a temperature in the approximaterange of 0°-35° C. for from approximately two to approximately sixhours. The 3-[2-hydroxy-4-(R)₂ aminophenyl]-3-(2-R³ -4-R¹-5-anilinophenyl)-5/6-carboxyphthalides thus obtained are isolated byadding the reaction mixture to ice-water and collecting the solid thusformed by filtration.

In accordance with a second of the process aspects of this invention,the 2-anilino-3-R¹ -6-(R)₂ amino-5'/6'-carboxyfluorans of Formula Iwherein Y is OH can be conveniently obtained by heating the appropriate3-[2-hydroxy-4-(R)₂ aminophenyl]-3-(2-R³ -4-R¹-5-anilinophenyl)-5/6-carboxyphthalide in the presence of an alkalimetal hydroxide, for example, sodium hydroxide or potassium hydroxide ina reaction medium, for example, dimethylsulfoxide at a temperature inthe approximate range of 50°-80° C. for a period of approximately one toapproximately three hours. The product is isolated by adding diluteaqueous sodium chloride to the reaction mixture followed byacidification with a dilute mineral acid, for example, hydrochloric acidand the product is collected by filtration.

In accordance with a third process aspect of the invention, the2-anilino-3-R¹ -6-(R)₂ amino-5'/6'-R² O-carbonyfluorans of Formula Iwherein R² is non-tertiary C₁ to C₁₈ alkyl or benzyl are obtained byinteracting a 2-anilino-3-R¹ -6-(R)₂ amino-5'/6'-carboxyfluoran with anappropriate alkylating agent, for example, dimethyl sulfate, diethylsulfate, ethyl iodide, n-butyl bromide, n-octyl bromide, n-hexadecylbromide, benzyl bromide, and the like in an inert diluent, for example,N,N-dimethylformamide in the presence of an alkali metal hydroxide orcarbonate, for example, sodium hydroxide, potassium hydroxide, sodiumcarbonate or potassium carbonate. The reaction is conveniently carriedout at a temperature in the approximate range of 30°-60° C. forapproximately one-half to three hours. The 2-anilino-3-R¹ -6-(R)₂amino-5'/6'-R² O-carbonylfluoran thus obtained is isolated by slowlyadding the reaction mixture to dilute aqueous sodium chloride andammonia solution. The product which separates is then collected byfiltration.

The 4/5-carboxyl-2-[4-(R)₂ amino-2-hydroxybenzoyl]benzoic acids havingthe formula ##STR8## required for the preparation of the3-[2-hydroxy-4-(R)₂ aminophenyl]-3-2-R³ -4-R¹-5-anilinophenyl)-5/6-carboxyphthalides of Formula II are generallyknown or if specifically new can be prepared in accordance with theprocedures described for the preparation of the known compounds, forexample, as disclosed in British Pat. No. 1,427,318, published Mar. 10,1976, i.e., by interacting trimellitic anhydride with an appropriatem-(R)₂ aminophenol in an inert diluent, for example, toluene or ethylenedichloride wherein R has the meanings given in relation to Formula Iabove.

It will, of course, be appreciated that the reaction of trimelliticanhydride with a m-(R)₂ aminophenol can produce isomers or a mixture ofisomers, viz. 4-carboxy-2-[4-(R)₂ amino-2-hydroxybenzoyl]benzoic acidsand 5-carboxy-2-[4-(R)₂ amino-2-hydroxybenzoyl]-benzoic acids. In thelatter instance, the isomeric mixtures of the benzoic acids can beseparated by conventional means such as fractional crystallization orchromatography. Alternatively, the isomeric mixture of the 4/5-carboxybenzoic acids can be reacted with the appropriate 2-R¹ -4-R₃-diphenylamine to produce a mixture of 5- and 6-carboxyphthalides ofFormula II which, if desired, can be separated or simply used as amixture in preparing the final products of Formula I. Throughout thisapplication where the possibility of different isomeric products beingformed is present, the nomenclature 4/5, 5/6 and 5'/6' is adoptedmeaning the product obtained or claimed is a mixture of the isomers.

The m-(R)₂ aminophenols, the 2-R¹ -4-R³ -diphenylamines and trimelliticanhydride required as starting materials in the processes of thisinvention belong to well known classes of compounds and are eithercommercially available or readily obtained by conventional procedureswell known in the art.

The molecular structures of the compounds were assigned on the basis ofthe modes of synthesis and a study of their infrared, nuclear magneticresonance, and mass spectra.

The following examples will further illustrate the invention without,however, limiting it thereto.

EXAMPLE 1

A. A mixture of 19.1 g (0.1 mole) of trimellitic anhydride, 16.5 g ofm-diethylaminophenol (0.1 mole) and 80.0 ml of dry ethylene dichloridewas heated at reflux for one hour. The reaction was then allowed to coolto room temperature and 100.0 ml of water and 22.0 ml of concentratedammonium hydroxide were added to the reaction mixture and the ethylenedichloride layer was separated from the basic aqueous layer. The aqueouslayer was extracted with 7.0 ml of petroleum ether to remove residueethylene dichloride and then nitrogen gas was bubbled into this aqueoussolution to remove residue petroleum ether. The alkaline extract wasacidified with dilute hydrochloric acid to pH 4.75 and the precipitatewhich separated was removed by filtration. The filtrate was thenadjusted to pH 3.0 and the separated solid was collected, washed withwater and dried to obtain 7.7 g of4/5-carboxy-2-(4-diethylamino-2-hydroxybenzoyl)benzoic acid (FormulaIII: R=CH₂ CH₃), an orange solid having a melting point of 188°-190° C.A significant maximum appeared in the ultraviolet spectrum at 353 nm.The infrared spectrum and the nuclear magnetic resonance spectrum werein accord with the structure.

B. To a stirred mixture of 42.0 ml of 100 percent sulfuric acid and 10.0ml of 18.9 percent oleum, there was added in small portions 16.0 g(0.045 mole) of 4/5-carboxy-2-(4-diethylamino-2-hydroxybenzoyl)benzoicacid prepared as described in part A above. The deep red solution wasthen cooled to 5° C., and 13.6 g (0.046 mole; 76.9 percent assay) of2-methyl-N-phenyl-p-phenetidine was added. The reaction mixture was thenmaintained at 15°-20° C. for an additional three and a half hours. Afterdrowning the reaction mixture in 700.0 ml of ice-water, the solid whichformed was collected by filtration, washed with water and dried toobtain 28.7 g of3-(2-hydroxy-4-diethylaminophenyl)-3-(2-ethoxy-4-methyl-5-anilinophenyl)-5/6-carboxyphthalide(Formula II: R=CH₂ CH₃ ; R¹ =CH₃ ; R³ =OCH₂ CH₃ ; a purple solid whichmelted with decomposition at 180°-190° C. Infrared maxima appeared at1765 cm⁻¹ (C═O;s) and 1715 cm⁻¹ (C═O;s).

C. To a solution of 32.4 g (71 percent pulp) of3-(2-hydroxy-4-diethylaminophenyl)-3-(2-ethoxy-4-methyl-5-anilinophenyl)-5/6-carboxyphthalide,described in part B of this example, in 150.0 ml of dimethylsulfoxide,there was added 23.0 g of 50 percent aqueous sodium hydroxide solutionat such a rate as to allow the reaction to exotherm to 50° C. After theaddition was complete, the solution was heated to 70° C. and held therefor a period of one hour and then allowed to cool to 25° C. Aftertreatment with decolorizing charcoal, the solution was quenched with950.0 ml of 5 percent aqueous salt solution. The alkaline solution wasthen acidified with dilute hydrochloric acid to pH 3.5 and the separatedsolid collected, washed with water and dried to obtain 13.1 g of2-anilino-3-methyl-6-diethylamino-5'/6'-carboxyfluoran (Formula I: R=CH₂CH₃ ; R¹ =CH₃ ; Y=OH), a black solid which melted with decomposition at110°-115° C. Infrared maxima appeared at 1760 cm⁻¹ (C═O;s) and 1705 cm⁻¹(C═O;s).

D. Six grams of diethyl sulfate was added to a preheated (40° C.)mixture of 10.4 g of the2-anilino-3-methyl-6-diethylamino-5'/6'-carboxyfluoran prepared asdescribed in part C above, 5.2 g of potassium carbonate and 50.0 ml ofdimethylformamide. The reaction mixture was heated at 45° C. for aperiod of one-half hour. After treatment with decolorizing charcoal, thedimethylformamide filtrate was slowly added to a solution of 400.0 ml of5 percent aqueous salt solution plus 10.0 ml of concentrated ammoniumhydroxide. The solid which separated was collected by filtration, washedwith water and dried to obtain 6.8 g of2-anilino-3-methyl-6-diethylamino-5'/6'-ethoxycarbonylfluoran (FormulaI: R=CH₂ CH₃ ; R¹ =CH₃ ; Y=OC₂ H₅), as a light purple solid melting overthe range 104°-107° C. Infrared maxima appeared at 1768 cm⁻¹ (C═O;s) and1725 cm⁻¹ (C═O;s). A toluene solution of the product spotted on silicagel, an acidic clay or a phenoic resin developed a black-colored image.

EXAMPLE 2

Five milliliters of dimethylsulfate was added to a preheated (45° C.)mixture of 5.0 g of the2-anilino-3-methyl-6-diethylamino-5'/6'-carboxyfluoran, prepared asdescribed in Example 1, part C above, 50.0 of potassium carbonate and150.0 ml of dimethylformamide. The reaction mixture was heated at 45° C.for a period of one hour and was then poured into water and extractedwith toluene. The toluene extract was washed successively with water andsaturated salt solution and then evaporated to dryness. The residue wastriturated with hexane and the solid separated and dried to obtain 2.4 gof 2-anilino-3-methyl-6-diethylamino-5'/6'-methoxycarbonylfluoran(Formula I: R=CH₂ CH₃ ; R¹ =CH₃ ; Y=OCH₃) as a light gray solid meltingover the range of 87°-98° C. Infrared maxima appeared at 1765 cm⁻¹(C═O;s) and 1725 cm⁻¹ (C═O;s). A toluene solution of the product spottedon silica gel, an acidic clay or a phenolic resin developed ablack-colored image.

EXAMPLE 3

Following a procedure similar to that described above in Example 2,except that α-bromotoluene was used in place of dimethylsulfate, therewas obtained2-anilino-3-methyl-6-diethylamino-5'/6'-phenylmethoxycarbonylfluoran(Formula I: R=CH₂ CH₃ ; R¹ =CH₃ ; Y=OCH₂ C₆ H₅) , a light brown solidmelting over the range 65°-94.5° C. Infrared maxima appeared at 1762cm⁻¹ (C═O;s) and 1720 cm⁻¹ (C═O;s) A toluene solution of the productspotted on silica gel, an acidic clay or a phenolic resin developed ablack-colored image.

EXAMPLE 4

Employing a procedure similar to that described in Example 2 butsubstituting n-butylbromide for α-bromotoluene, there was obtained2-anilino-3-methyl-6-diethylamino-5'/6'-n-butoxycarbonylfluoran (FormulaI: R=CH₂ CH₃ ; R¹ =CH₃ ; Y=O--n--C₄ H₉), a light purple solid meltingover the range 76°-83° C. Infrared maxima appeared at 1765 cm⁻¹ (C═O;s)and 1725 cm⁻¹ (C═O;s). A toluene solution of the product spotted onsilica gel, an acidic clay or a phenolic resin developed a black-coloredimage.

EXAMPLE 5

When 1-bromohexadecane was substituted for α-bromotoluene in Example 2,there was obtained2-anilino-3-methyl-6-diethylamino-5'/6'-n-hexadecyloxycarbonylfluoran(Formula I: R=CH₂ CH₃ ; R¹ =CH₃ ; Y=O--n--C₁₆ H₃₃) as a purple oil.Analysis by mass spectrum showed m/e peaks at 744 (m+) and 700(m+--CO₂). A toluene solution of the product spotted on silica gel, anacidic clay or a phenolic resin developed a black-colored image.

EXAMPLE 6

A. Employing a procedure similar to that described in part B of Example1, 30.0 g (0.084 mole) of4/5-carboxy-2-(4-diethylamino-2-hydroxybenzoyl)benzoic acid, prepared asdescribed in part A of Example 1, was interacted with 23.5 g (0.11 mole)of N-phenyl-p-phenetidine to obtain 49.0 g of3-(2-hydroxy-4-diethylaminophenyl)-3-(2-ethoxy-5-anilinophenyl)-5/6-carboxyphthalide(Formula II: R=CH₂ CH₃ ; R¹ =H; R³ =OCH₂ CH₃) a purple solid whichmelted with decomposition at 98°-155° C. Infrared maxima appeared at1762 cm⁻¹ (C═O;s) and 1732 cm⁻¹ (C═O;s).

B. Following a procedure similar to that described in Example 1, part Cabove, except that 10.0 g of3-(2-hydroxy-4-diethylaminophenyl)-3-(2-ethoxy-5-anilinophenyl)-5/6-carboxyphthalide,prepared as described in part A of this example, was used in place of3-(2-hydroxy-4-diethylaminophenyl)-3-(2-ethoxy-4-methyl-5-anilinophenyl)-5/6-carboxyphthalide,there was obtained 5.8 g of2-anilino-6-diethylamino-5'/6'-carboxyfluoran (Formula I: R=CH₂ CH₃ ; R¹=H; Y=OH), a purple solid which melted with decomposition at 135°-148°C. Infrared maxima appeared at 1756 cm⁻¹ (C═O;s) and 1705 cm⁻¹ (C═O;s).

C. Employing a procedure similar to that described in Example 2, butinteracting 5.0 g of 2-anilino-6-diethylamino-5'/6'-carboxyfluoranprepared as described in Part B of this example with dimethyl sulfate,there was obtained 2.1 g of2-anilino-6-diethylamino-5'/6'-methoxycarbonylfluoran (Formula I: R=CH₂CH₃ ; R¹ =H; Y=OCH₃), a gray solid melting over the range 71°-76° C.Infrared maxima appeared at 1765 cm⁻¹ (C═O;s) and 1730 cm⁻¹ (C═O;s).Analysis by mass spectrum showed m/e peaks at 520 (m⁺), 476 (m⁺ --CO₂)and 461 (m⁺ --COOCH₃). A toluene solution of the product spotted onsilica gel, an acidic clay or a phenolic resin developed agreen-black-colored image.

EXAMPLE 7

When diethylsulfate was substituted for dimethylsulfate for interactionwith 10.0 g of 2-anilino-6-diethylamino-5'/6'-carboxyfluoran accordingto the procedure described in part C of Example 6, there was obtained5.1 g of 2-anilino-6-diethylamino-5'/6'-ethoxycarbonylfluoran (FormulaI: R=CH₂ CH₃ ; R¹ =H; Y=OCH₂ CH₃), a light grape-colored solid meltingover the range 70°-85° C. Infrared maxima appeared at 1768 cm⁻¹ (CO═O;s)and 1720 cm⁻¹ (C═O;s). The nuclear magnetic resonance spectrum was inagreement with the assigned structure. Analysis by mass spectrum showedm/e peaks at 534 (m⁺), 489 (m⁺ --COOH) and 461 (m⁺ --COOC₂ H₅). Atoluene solution of the product spotted on silica gel, an acidic clay ora phenolic resin developed a green-black-colored image.

EXAMPLE 8

A. Following a procedure similar to that described above in part A ofExample 1 but substituting m-dimethylaminophenol form-diethylaminophenol, there was obtained4/5-carboxy-2-(4-dimethylamino-2-hydroxybenzoyl)benzoic acid (FormulaIII: R=CH₃), a yellow solid having a melting point of 233°-236° C. Theinfrared spectrum and the nuclear magnetic resonance spectrum were inaccord with the structure. Analysis by mass spectrum showed m/e peaks at329 (m⁺) and 284 (m^(+--COOH)).

B. A mixture of 16.5 g (0.05 mole) of4/5-carboxy-2-(4-dimethylamino-2-hydroxybenzoyl)benzoic acid from part Aabove, and concentrated sulfuric acid was interacted withN-phenyl-p-phenetidine in a manner similar to that described above inExample 6, part A to obtain 17.5 g of3-(2-hydroxy-4-dimethylaminophenyl)-3-(2-ethoxy-5-anilinophenyl)-5/6-carboxyphthalide(Formula II: R=CH₃ ; R¹ =H; R³ =OCH₂ CH₃), a purple solid which meltedwith decomposition at 119°-134° C. Infrared maxima appeared at 1770 cm⁻¹(C═O;s) and 1715 cm⁻¹ (C═O;s).

C. Proceeding in a manner similar to part C of Example 6, butsubstituting 16.7 g of3-(2-hydroxy-4-dimethylaminophenyl)-3-(2-ethoxy-5-anilinophenyl)-5/6-carboxyphthalide,prepared as described in part B above, for3-(2-hydroxy-4-diethylaminophenyl)-3-(2-ethoxy-5-anilinophenyl)-5/6-carboxyphthalide,there was obtained 7.5 g of2-anilino-6-dimethylamino-5'/6'-carboxyfluoran (Formula I: R=CH₃ ; R¹=H; Y=OH), a purple solid melting at 180°-183° C. Infrared maximaappeared at 1760 cm⁻¹ (C═O;s) and 1690 cm⁻¹ (C═O;s). Analysis by massspectrum showed m/e/ peaks at 478 (m⁺) and at 433 (m⁺ --COOH).

D. Employing a procedure similar to that described in Example 2, butinteracting 5.0 g of 2-anilino-6-dimethylamino-5'/6'-carboxyfluoran,prepared as described in part C of this example, with dimethyl sulfatethere was obtained 1.8 g of2-anilino-6-dimethylamino-5'/6'-methoxycarbonylfluoran (Formula I: R=CH₃; R¹ =H; Y=OCH₃), a gray solid melting over the range 97.5°-115° C.Infrared maxima appeared at 1763 cm⁻¹ (C═O;s) and 1725 cm⁻¹ (C═O;s).Analysis by mass spectrum showed m/e peaks at 492 (m⁺), 448 (m⁺ --CO₂)and 433 (m⁺ --COOCH₃). A toluene solution of the product spotted onsilica gel, an acidic clay or a phenolic resin developed agreen-black-colored image.

It is contemplated that by following the procedure described in Example1, part B above, but using in place of4/5-carboxy-2-(4-diethylamino-2-hydroxybenzoyl)benzoic acid and2-methyl-N-phenyl-p-phenetidine approximately molar equivalentquantities of the appropriate 4/5-carboxy-2-[4-(R)₂amino-2-hydroxybenzoyl]benzoic acid and the appropriate 2-R¹ -4-R³-diphenylamine the following 3-[2-hydroxy-4-(R)₂ aminophenyl]-3-(2-R³-4-R¹ -5-anilinophenyl)-5/6-carboxyphthalides of Formula II described inExamples 9-12 are obtained.

EXAMPLE 9

3-(2-Hydroxy-4-di-n-propylaminophenyl)-3-(2-methoxy-4-ethyl-5-anilinophenyl)-5/6-carboxyphthalideusing 4/5-carboxy-2-(4-di-n-propylamino-2-hydroxybenzoyl)benzoic acidand 2-ethyl-4-methoxydiphenylamine.

EXAMPLE 10

3-(2-Hydroxy-4-di-s-butylaminophenyl)-3-(2-n-butoxy-5-anilinophenyl)-5/6-carboxyphthalideusing 4/5-carboxy-2-(4-di-s-butylamino-2-hydroxybenzoyl)benzoic acid and4-n-butoxydiphenylamine.

EXAMPLE 11

3-(2-Hydroxy-4-di-i-propylaminophenyl)-3-(2-n-propoxy-4-n-butyl-5-anilinophenyl)-5/6-carboxyphthalideusing 4/5-carboxy-2-(4-di-i-propylamino-2-hydroxybenzoyl)benzoic acidand 4-n-propoxy-2-n-butyldiphenylamine.

EXAMPLE 12

3-(2-Hydroxy-4-di-n-butylaminophenyl)-3-(2-s-butoxy-4-methyl-5-anilinophenyl)-5/6-carboxyphthalideusing 4/5-carboxy-2-(4-di-n-butylamino-2-hydroxybenzoyl)benzoic acid and4-s-butoxy-2-methyldiphenylamine.

It is contemplated that by following the procedure described in Example1, part C above, but using in place of3-(2-hydroxy-4-diethylaminophenyl)-3-(2-ethoxy-4-methyl-5-anilinophenyl)-5/6-carboxyphthalideand sodium hydroxide the appropriate 3-[2-hydroxy-4-(R)₂aminophenyl]-3-(2-R³ -4-R¹ -5-anilinophenyl)-5/6-carboxyphthalide andalkali metal hydroxide or ammonium hydroxide the following2-anilino-3-R¹ -6-(R)₂ amino-5'/6'-carboxyfluorans of Formula I whereinY is OH described in Examples 13-16 are obtained.

EXAMPLE 13

2-Anilino-3-ethyl-6-di-n-propylamino-5'/6'-carboxyfluoran using3-(2-hydroxy-4-di-n-propylaminophenyl)-3-(2-methoxy-4-ethyl-5-anilinophenyl)-5/6-carboxyphthalideand potassium hydroxide.

EXAMPLE 14

2-Anilino-6-di-s-butylamino-5'/6'-carboxyfluoran using3-(2-hydroxy-4-di-s-butylaminophenyl)-3-(2-n-butoxy-5-anilinophenyl)-5/6-carboxyphthalideand lithium hydroxide.

EXAMPLE 15

2-Anilino-3-n-butyl-6-di-i-propylamino-5'/6'-carboxyfluoran using3-(2-hydroxy-4-di-i-propylaminophenyl)-3-(2-n-propoxy-4-n-butyl-5-anilinophenyl)-5/6-carboxyphthalideand ammonium hydroxide.

EXAMPLE 16

2-Anilino-3-methyl-6-di-n-butylamino-5'/6'-carboxyfluoran using3-(2-hydroxy-4-di-n-butylaminophenyl)-3-(2-s-butoxy-4-methyl-5-anilinophenyl)-5/6-carboxyphthalideand potassium hydroxide.

It is contemplated that by following the procedure described in Example1, part D above, but using in place of2-anilino-3-methyl-6-diethylamino-5'/6'-carboxyfluoran and diethylsulfate the appropriate 2-anilino-3-R¹ -6-(R)₂amino-5'/6'-carboxyfluoran and the appropriate compound selected fromthe group consisting of dimethyl sulfate, diethyl sulfate, non-tertiaryC₁ to C₁₈ alkyl halogen or benzyl halide the following 2-anilino-3-R¹-6-(R)₂ amino-5'/6'-Y-carbonylfluoran of Formula I wherein Y representsR² O in which R² is a non-tertiary C₁ to C₁₈ alkyl or benzyl describedin Examples 17-21 are obtained.

EXAMPLE 17

2-Anilino-3-ethyl-6-di-n-propylamino-5'/6'-n-hexyloxycarbonylfluoranusing 2-anilino-3-ethyl-6-di-n-propylamino-5'/6'-carboxyfluoran andn-hexylbromide.

EXAMPLE 18

2-Anilino-6-di-s-butylamino-5'/6'-n-octadecyloxycarbonylfluoran using2-anilino-6-di-s-butylamino-5'/6'-carboxyfluoran and n-octadecylbromide.

EXAMPLE 19

2-Anilino-3-n-butyl-6-di-i-propylamino-5'/6'-i-octyloxycarbonylfluoranusing 2-anilino-3-n-butyl-6-di-i-propylamino-5'/6'-carboxyfluoran andi-octylbromide.

EXAMPLE 20

2-Anilino-3-methyl-6-di-n-butylamino-5'/6'-n-dodecyloxycarbonylfluoranusing 2-anilino-3-methyl-6-di-n-butylamino-5'/6'-carboxyfluoran andn-dodecyliodide.

EXAMPLE 21

The use of the fluoran compounds of Formula I and described in Examples1 through 20 as color forming components in pressure-sensitivemicroencapsulated copying system is illustrated with reference to theproduct of Example 8D.

A. A mixture of 196.0 ml of distilled water and 15.0 g of pigskingelatin was stirred at approximately 50° C. for approximately 45minutes. There was then added to the mixture a warmed (approximately 50°C.) solution of 49.0 g of alkylated biphenyls and 1.0 g of2-anilino-6-dimethylamino-5'/6'-methoxycarbonylfluoran prepared asdescribed above in Example 8D. The resulting solution was stirred forapproximately fifteen minutes. A second solution of 81.0 ml of distilledwater and 5.0 g of carboxymethylcellulose was then prepared and warmedto approximately 50° C. for approximately one hour.

B. The two solutions, the first containing water, gelatin, alkylatedbiphenyls and the product, and the second containing water withcarboxymethylcellulose were mixed by means of an Eppenbach Homo-Mixer(Gifford-Wood Co., Hudson, N.Y.). The pH was adjusted to 6.5 by theaddition of approximately 0.7 ml of 20 percent aqueous sodium hydroxide.To the resultant mixture was added over a period of two to three minutes650.0 ml of distilled water which had been heated to 50° C. With thestirrer running at an applied voltage of between 35 to 40 volts therewas slowly added sufficient ten percent aqueous acetic acid to set thepH at 4.5, this being the point where coacervation was initialed. Fourdrops of 2-ethylhexanol were added to suppress foaming. Afterapproximately twenty minutes an external ice-water bath was placedaround the reactor containing the suspension. Cooling was continued andat approximately 15° C., 10.0 ml of glutaraldehyde was added over aperiod of five minutes. When the internal temperature reached 10° C.,the Eppenbach Homo-Mixer was replaced with a conventional blade typelaboratory agitator and the thus prepared suspension of microcapsuleswas stirred an additional three hours during which period thetemperature was allowed to warm to room temperature.

C. The microcapsule suspension prepared as described in part B above wascoated on paper sheets to a thickness of approximately 0.0015 inch andthe coated paper aid dried. The paper thus coated with themicroencapsulated colorless precursor was assembled as the top sheet ina manifold system by positioning the coated side in contact with thecoated side of a commercially available receiving sheet coated with acolor developer of the electron accepting type. More specifically,papers coated with a phenolic resin and with an acidic clay wereemployed in this test. An image was then drawn with a stylus on the topsheet bearing the microencapsulated colorless precursor on its reverseside causing the affected microcapsules to rupture thus allowing thesolution of the colorless precursor held by said microcapsules to flowinto contact with the color developing substance on the receiving sheetwhereupon a deep green-colored image promptly formed.

When evaluated in a duplicating system prepared and tested as describedabove, the product of Example 2,2-anilino-3-methyl-6-diethylamino-5'/6'-methoxycarbonylfluoran, produceda black-colored developed image.

EXAMPLE 22

The utility of the fluorans of Formula I and the phthalides of FormulaII whose preparations are described in the foregoing examples as colorforming components in thermal marking systems is illustrated by theincorporation and testing of the compounds of Example 6C and of Example1B, respectively, in a thermal sensitive marking paper. The test paperwas prepared by a procedure similar to that described in U.S. Pat. No.3,539,375.

A. A mixture of 2.0 g of2-anilino-6-diethylamino-5'/6'-methoxycarbonylfluoran, 8.6 g of a tenpercent aqueous solution of polyvinyl alcohol (approximately 99 percenthydrolyzed), 3.7 g of water and 31.6 g of 1/16 inch diameter zirconiumgrinding beads was charged into a container which was placed in amechanical shaker. Shaking was effected for one hour. The zirconiumbeads were then removed by straining the mixture through a No. 40 sieve.

B. Similarly, a mixture of 9.8 g of 4,4'-isopropylidine diphenol(Bisphenol A), 42.0 g of a ten percent aqueous polyvinyl alcoholsolution (approximately 99 percent hydrolyzed), 18.2 g of water and221.2 g of 1/16 inch diameter zirconium grinding beads was charged intoa container which was placed in a mechanical shaker. After shaking waseffected for one hour, the zirconium beads were removed by strainingthrough a No. 40 sieve.

C. A coating composition was prepared by mixing 2.1 g of the slurry fromA and 47.9 g of the slurry from B. The mixture was then uniformly coatedon sheets of paper at thicknesses of approximately 0.003 inch and thecoated sheets air-dried. The coated paper was tested by tracing a designon the coated side of the paper placed on a smooth flat surface with astylus heated to approximately 125° C. A deep green-black-colored imagecorresponding to the traced design promptly developed. When evaluated inthermal marking paper prepared and tested as described above, theproduct of Example 1B,3-(2-hydroxy-4-diethylaminophenyl)-3-(2-ethoxy-4-methyl-5-anilinophenyl)-5/6-carboxyphthalide,produced a brown-black-colored image.

What is claimed is:
 1. A pressure-sensitive carbonless duplicatingsystem or thermal marking system comprising a support sheet coated witha layer containing as a color-forming substance a 2-anilino-3-R¹ -6-(R)₂amino-5'/6'-Y-carbonylfluoran of the formula ##STR9## wherein: Rrepresents a non-tertiary C₁ to C₄ alkyl;R¹ represents hydrogen or anon-tertiary C₁ to C₄ alkyl; and Y represents OR² in which R² representshydrogen, a non-tertiary C₁ to C₁₈ alkyl, benzyl, alkali metal cation orammonium cation.
 2. A pressure-sensitive carbonless duplicating systemor thermal making system according to claim 1 containing as acolor-forming substance a 2-anilino-3-R¹ -6-(R)₂ amino-5'/6'-R²O-carbonylfluoran wherein R² represents a non-tertiary C₁ to C₁₈ alkylor benzyl and R and R¹ each have the same respective meanings given inclaim
 1. 3. A pressure-sensitive carbonless duplicating system orthermal marking system according to claim 2 containing as acolor-forming substance2-anilino-3-methyl-6-diethylamino-5'/6'-methoxycarbonylfluoran.
 4. Apressure-sensitive carbonless duplicating system or thermal markingsystem according to claim 2 containing as a color-forming substance2-anilino-6-dimethylamino-5'/6'-methoxycarbonylfluoran.
 5. Apressure-sensitive carbonless duplicating system or thermal markingsystem according to claim 2 containing as a color-forming substance2-anilino-6-diethylamino-5'/6'-methoxycarbonylfluoran.
 6. Apressure-sensitive carbonless duplicating system according to claim 2comprising a support sheet coated on one side with a layer ofpressure-rupturable microcapsules containing a liquid solution of thecolor-forming substance.
 7. A thermal marking system according to claim2 comprising a support sheet coated on one side with a layer containinga mixture of the color-forming substance and an acidic developerarranged such that application of heat will produce a mark-formingreaction between the color-forming substance and the acidic developer.8. A thermal marking system comprising a support sheet coated with alayer containing as a color-forming substance a 3-[2-hydroxy-4 -(R)₂aminophenyl]-3-(2-R³ -4-R¹ -5-anilinophenyl)-5/6-carboxyphthalide of theformula ##STR10## wherein: R represents a non-tertiary C₁ to C₄ alkyl;R¹represents hydrogen or a non-tertiary C₁ to C₄ alkyl; and R₃ representsa non-tertiary C₁ to C₄ alkoxy.
 9. A thermal marking system according toclaim 8 containing as a color-forming substance3-(2-hydroxy-4-diethylaminophenyl)-3-(2-ethoxy-4-methyl-5-anilinophenyl)-5/6-carboxyphthalide.10. A thermal marking system according to claim 8 comprising a supportsheet coated on one side with a layer containing a mixture of thecolor-forming substance and an acidic developer arranged such thatapplication of heat will produce a mark-forming reaction between thecolor-forming substance and the acidic developer.